print backtrace when loging xdc rep manager exception
print backtrace when loging xdc rep manager exception

Change-Id: I3aadc01658cbe9fe5611852142bdaa7cc84c0f77
Reviewed-on: http://review.couchbase.org/10403
Tested-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>
Reviewed-by: Aliaksey Artamonau <3c875bcfb3adf2a65b2ae7686ca921e6c9433147@gmail.com>
Reviewed-by: Srinivas Vadlamani <4036f57732a648e71da3ac2c829c8239a16a4c5d@couchbase.com>

t3rm1n4l/ns_server,t3rm1n4l/ns_server,nimishzynga/ns_server,daverigby/ns_server,mschoch/ns_server,ceejatec/ns_server,membase/ns_server,vzasade/ns_server,pavel-blagodov/ns_server,ceejatec/ns_server,ceejatec/ns_server,nimishzynga/ns_server,vzasade/ns_server,pavel-blagodov/ns_server,vzasade/ns_server,membase/ns_server,ceejatec/ns_server,daverigby/ns_server,membase/ns_server,nimishzynga/ns_server,mschoch/ns_server,nimishzynga/ns_server,daverigby/ns_server,membase/ns_server,t3rm1n4l/ns_server,nimishzynga/ns_server,t3rm1n4l/ns_server,nimishzynga/ns_server,ceejatec/ns_server,mschoch/ns_server,membase/ns_server,t3rm1n4l/ns_server,mschoch/ns_server,membase/ns_server,mschoch/ns_server,mschoch/ns_server,ceejatec/ns_server,pavel-blagodov/ns_server,pavel-blagodov/ns_server,daverigby/ns_server,vzasade/ns_server,daverigby/ns_server